Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), College of Environmental Science and Engineering, Nankai University, Tianjin, China.
Tianjin Key Lab Clean Energy & Pollutant Control, School of Energy and Environmental Engineering, Hebei University of Technology, 300130, Tianjin, China.
Nat Commun. 2023 Jun 15;14(1):3538. doi: 10.1038/s41467-023-39228-4.
In heterogeneous catalysis, uncovering the dynamic evolution of active sites in the working conditions is crucial to realizing increased activity and enhanced stability of catalyst in Fenton-like activation. Herein, we capture the dynamic changes in the unit cell of Co/La-SrTiO catalyst during the exemplary peroxymonosulfate activation process using X-ray absorption spectroscopy and in situ Raman spectroscopy, revealing the substrate tuned its structural evolution, which is the reversible stretching vibration of O-Sr-O and Co/Ti-O bonds in different orientations. This process effectively promotes the generation of key SO* intermediates, which is beneficial to the formation of O and SO from persulfate on the Co active site. Density functional theory and X-ray absorption spectroscopy show that the optimized structural distortion enhanced the metal-oxygen bond strength by tuning the e orbitals and increased the number of transferred electrons to peroxymonosulfate by about 3-fold, achieving excellent efficiency and stability in removing organic pollutants.
在多相催化中,揭示活性位在工作条件下的动态演变对于实现 Fenton 样活化中催化剂活性的提高和稳定性的增强至关重要。在此,我们使用 X 射线吸收光谱和原位拉曼光谱捕捉到 Co/La-SrTiO 催化剂在典型过一硫酸盐活化过程中单元晶胞的动态变化,揭示了基质对其结构演变的调控,这是 O-Sr-O 和不同取向的 Co/Ti-O 键的可逆伸缩振动。这一过程有效地促进了关键 SO*中间体的生成,有利于过硫酸盐在 Co 活性位上生成 O 和 SO。密度泛函理论和 X 射线吸收光谱表明,优化的结构变形通过调整 e 轨道增强了金属-氧键的强度,并将过一硫酸盐的转移电子数增加了约 3 倍,从而在去除有机污染物方面表现出优异的效率和稳定性。